Crank bearings? Do they need replacing?

[Snow]

Hi All,
I've still got my engine cases split and *still* waiting on my left seal...anyhew, when I pulled the cases apart, one of the bearings fell off and I put it right back where it belongs in the correct orientation...however... I think I notcied that it was two colors where the crank rides - I think it was silver and a bit of copper...would this mean I need to replace my bearings?

[DiverRay]

You may need to. If it's apart, I would do a quick check with plastigauge. It should only take about 1/2 hour, and will tell you for sure.
If you are the one who just got the crank bearing kit from ebay, I just got the rod kit. The crank will only need one of the sizes, so we may be able to trade parts once I start the rebuild on my spare engine.
Ray

[randy]

Snow,

The copper is the base metal, so that bearing is worn through the tin cladding and needs to be replaced. Ray is right, the plastiguage will tell you the clearance, but if you see copper, it's trashed.

[Shappers]

Sorry DiverRay that was me

You almost maxed me out there I am in the middle of rebuilding my Sport engine at the moment. I found my crank was badly worn on the mains so I got another crankshaft from Germany, hence the need for a new set of crank bearings.

From the numbers it looks like I will need 2 blacks and 3 browns out of the kit but I plan on checking with plastiguage as well. I thought that once I am sorted I would offer the rest for sale as I'm sure depending on what is used there might be enough left to maybe sort out another crankshaft.

DiverRay, perhaps we could swap the leftovers? Crank for Conrod bearings!

Brgds, Shappers.

[ccogswel]

If you all don't mind me throwing my two cents worth in, but if you use the plastigauge just make sure you clean all the oil off the crank and every surface for the bearings as it can give you false readings. Also rotate the crank 180 degrees and check again. Good luck!

[randy]

Ray,

Which color crank bearing(s) do you need? I have a full set.

[Shappers]

Originally posted by ccogswel
If you all don't mind me throwing my two cents worth in, but if you use the plastigauge just make sure you clean all the oil off the crank and every surface for the bearings as it can give you false readings. Also rotate the crank 180 degrees and check again. Good luck!

Hi Chris,

Thanks for this advice, I didn't realise this. I just got some plastiguage but I have never used it before.

Brgds, Shappers.

[Pat Kelly]

Don't rotate the crank with the plastigage in it. Remove and remeasure with another bit-o-plastigage. (I know you already knew that but I felt compelled to say it anyway)

[ccogswel]

Hi Shappers, You are welcome. Just glad to be able to help a little.

Pat, You are right, Thanks for jumping in. Better safe then sorry.

After all how many times have we all had to redo something twice over something so simple.

Or is it just my luck

[DiverRay]

Randy,
I have NOT started the engine rebuild yet. I'm just trying to get the parts together. Once I have the crank checked, I'll know what I need. It may be a few months, as I don't have the cash to work on everything at once.
Thanks for the offer, and I may pm you once I get there.
Ray